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Full text of "Practical Organic Chemistry"

APPENDIX

bases with tertiary aromatic amines (see p. 157), which dissolve
in water in presence of hydrochloric acid, with which they form
soluble hydrochlorides. Tertiary amines also combine with
methyl iodide on warming (see Reaction, p. 157), but not with
acetyl chloride. Primary amines give the carbamine reaction
(p. 150), and unite with carbon bisulphide (p. 159).
Oximcs.It should be remembered that oximes act as bases
as well as acids, and dissolve in both caustic alkalis and acids.
On reduction in acid solution (with tin or zinc) they yield"
amines.
Cyanides and Amides are hydrolysed by caustic potash
(aqueous or, better, alcoholic), cone, hydrochloric or sulphuric
acid as mentioned previously under  I, 2. It should be mentioned
that some amides are attacked only with difficulty, and must then
be treated as described under  I, 2.
Nitre-compounds are frequently yellow or orange in
colour. Heated with stannous chloride in cone. HCl or zinc
dust and glacial acetic acid they dissolve and remain in solution
on the addition of water. The base which is thus formed maybe
separated by adding an excess of caustic soda'until the metallic
oxide dissolves and then shaking out with ether. When the
ether is removed, the base remains. If liquid, the base should
be converted into the acetyl derivative by warming with acetyl
chloride for a few minutes and pouring into water. The free
base or solid acetyl. derivative, as the case may be, should be
recrystallised and the melting-point determined. It can also be
diazotised and coupled with p-naphthol.
Alky I Nitrates are hydrolysed like other esters, and yield
alcohol and nitric acid (p. 82).
Nitro-phenols and Nitro-adds dissolve in caustic alkalis
as a rule with a deep yellow or orange colour. On re-
duction with stannous chloride or zinc dust, as described
above, they yield the amino-derivatives. In the case of the
ammo-phenol, the solution is made alkaline with caustic soda,
saturated with CCX, salt added and extracted with ether. In
the case of the ainino-acid, the method used is that described
under Prep. 91 (p. 201).
Aso- and Azoxy-compounds. Both classes of compounds
rre usually highly coloured and are rapidly decolorised by
winning with a solution of stannous chloride and hydrochloric
acid, forming amino-colnpounds (see Reactions, pp. I73> J77)-